Computer network telemetry data can provide information enabling network administrators to quickly diagnose and correct issues with network connectivity. Some out-of-band mechanisms collect different node and network related data (e.g., resource utilization), but do not capture data on node-to-node communications. For instance, Internet Control Message Protocol (ICMP) messages play a role in any network to communicate error/informational messages between nodes including Path Maximum Transmission Unit Discovery (PMTUD), Time-To-Live (TTL) expiry, parameter problems, Duplicate Address Detection (DAD), and/or neighbor discovery. In these examples, the transit network nodes directly send the error/informational messages to the original source address without the network operator obtaining a full view of the error/informational exchanges between different nodes.
Typical ICMP messages are generated at a transit node and sent to the original source of the packet, and are not included in typical telemetry available for network analysis. Network analysis is typically performed by reviewing ICMP error counters on transit nodes, which provide limited information on how many packets were dropped for, e.g., TTL expiry or Packet Too Big (PTB) errors in which a received packet is larger than the maximum transmission unit of the transit node. Some transit nodes may provide Netflow export data under some conditions, but neither error counters nor Netflow collection provides sufficiently granular telemetry information to completely characterize network operations.